Many of the advance ANSYS FLUENT users write UDF (User Defined Function) to ask ANSYS FLUENT to do some special jobs. These UDFs are very popular in ANSYS FLUENT user community. Most of the UDFs that we create are programmed for serial mode of ANSYS FLUENT since it only involves basic C program coding with required marcos. However, to utilize the power of parallel processing, we need to convert the serial UDF into parallel UDF. Read this blog for a step by step process to convert serial UDF to parallel UDF.

Hello Friends, its being a long time I haven't shared any new information on User Defined Functions (UDFs) available in ANSYS Fluent. Well that may make you think that UDFs are so tough to create, that this person took so long to write his second experience (blog) on UDF! Yeah, it’s funny, but let me tell that this is not the case with me, they (UDFs) are actually so interesting …and huge time & manual effort saver …and productive …and… I can go on and on if I start listing down all the plus points of using UDFs in Fluent. So, long story made short, I was fully enjoying past few months in learning and using this UDF & Scheme programming knowledge to Automate CFD studies in ANSYS Fluent.

Imagine you are working as a CFD Analyst/ Design Engineer in a leading automotive industry performing year round optimization studies on various aerodynamic aspects of car design. Definitely your job profile would be exciting and challenging but at the same time most of your tasks involve repetitive CFD procedures like same simulation strategy for various design changes. For such an CFD engineer automation and customization would be a great savior.

Having the basic introduction to writing a UDF from the earlier article "Writing a UDF for CFD Modeling" wherein we saw using UDF for inserting custom boundary profiles, we shall now see another application of UDF with an example of boiling phenomenon. To get the most understanding from the current article the reader should be familiar with ANSYS Fluent software and basic UDF understanding.

Writing a UDF i.e. a user defined function, has always been a challenging stuff for CFD engineers those have never tried out one, nevertheless has been a matter of interest for all. Hereby we present a short article to demonstrate the significance of writing a UDF in CFD modeling with a simple test case that would help us all to develop an understanding at the introductory level.